1. Field of the Invention
The invention relates to a positioning method, and more particularly to a free space positioning method and system.
2. Description of the Related Art
It has become popular to use a camera to acquire a position of an object in a three-dimensional (3D) space. For example, coordinates of an object in the 3D space may be obtained by: using a shape and a size of structured light projected onto the object to determine a position of the object; using a depth camera that employs a principle of time of flight (ToF) to calculate a distance between the object and the camera; and using a twin-lens camera to obtain two images for acquiring a depth of the object via parallax calculation. However, these methods are unable to detect an attitude angle (e.g., components of a yaw angle, a pitch angle and a roll angle) of the object.